regulator: max5970: Rename driver and remove wildcard

The previous version of this driver included wildcards in file names and
descriptions. This patch renames the driver to only support MAX5970 and
MAX5978, which are the only chips that the driver actually supports.

Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
Link: https://lore.kernel.org/r/20230801102453.1798292-1-Naresh.Solanki@9elements.com
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 514 insertions, 0 deletions

diff --git a/drivers/regulator/max5970-regulator.c b/drivers/regulator/max5970-regulator.c
new file mode 100644
index 000000000000..b56a174cde3d
--- /dev/null
+++ b/drivers/regulator/max5970-regulator.c
@@ -0,0 +1,514 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Device driver for regulators in MAX5970 and MAX5978 IC
+ *
+ * Copyright (c) 2022 9elements GmbH
+ *
+ * Author: Patrick Rudolph <patrick.rudolph@9elements.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/platform_device.h>
+
+#include <linux/mfd/max5970.h>
+
+struct max5970_regulator {
+	int num_switches, mon_rng, irng, shunt_micro_ohms, lim_uA;
+	struct regmap *regmap;
+};
+
+enum max597x_regulator_id {
+	MAX597X_SW0,
+	MAX597X_SW1,
+};
+
+static int max597x_uvp_ovp_check_mode(struct regulator_dev *rdev, int severity)
+{
+	int ret, reg;
+
+	/* Status1 register contains the soft strap values sampled at POR */
+	ret = regmap_read(rdev->regmap, MAX5970_REG_STATUS1, &reg);
+	if (ret)
+		return ret;
+
+	/* Check soft straps match requested mode */
+	if (severity == REGULATOR_SEVERITY_PROT) {
+		if (STATUS1_PROT(reg) != STATUS1_PROT_SHUTDOWN)
+			return -EOPNOTSUPP;
+
+		return 0;
+	}
+	if (STATUS1_PROT(reg) == STATUS1_PROT_SHUTDOWN)
+		return -EOPNOTSUPP;
+
+	return 0;
+}
+
+static int max597x_set_vp(struct regulator_dev *rdev, int lim_uV, int severity,
+			  bool enable, bool overvoltage)
+{
+	int off_h, off_l, reg, ret;
+	struct max5970_regulator *data = rdev_get_drvdata(rdev);
+	int channel = rdev_get_id(rdev);
+
+	if (overvoltage) {
+		if (severity == REGULATOR_SEVERITY_WARN) {
+			off_h = MAX5970_REG_CH_OV_WARN_H(channel);
+			off_l = MAX5970_REG_CH_OV_WARN_L(channel);
+		} else {
+			off_h = MAX5970_REG_CH_OV_CRIT_H(channel);
+			off_l = MAX5970_REG_CH_OV_CRIT_L(channel);
+		}
+	} else {
+		if (severity == REGULATOR_SEVERITY_WARN) {
+			off_h = MAX5970_REG_CH_UV_WARN_H(channel);
+			off_l = MAX5970_REG_CH_UV_WARN_L(channel);
+		} else {
+			off_h = MAX5970_REG_CH_UV_CRIT_H(channel);
+			off_l = MAX5970_REG_CH_UV_CRIT_L(channel);
+		}
+	}
+
+	if (enable)
+		/* reg = ADC_MASK * (lim_uV / 1000000) / (data->mon_rng / 1000000) */
+		reg = ADC_MASK * lim_uV / data->mon_rng;
+	else
+		reg = 0;
+
+	ret = regmap_write(rdev->regmap, off_h, MAX5970_VAL2REG_H(reg));
+	if (ret)
+		return ret;
+
+	ret = regmap_write(rdev->regmap, off_l, MAX5970_VAL2REG_L(reg));
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int max597x_set_uvp(struct regulator_dev *rdev, int lim_uV, int severity,
+			   bool enable)
+{
+	int ret;
+
+	/*
+	 * MAX5970 has enable control as a special value in limit reg. Can't
+	 * set limit but keep feature disabled or enable W/O given limit.
+	 */
+	if ((lim_uV && !enable) || (!lim_uV && enable))
+		return -EINVAL;
+
+	ret = max597x_uvp_ovp_check_mode(rdev, severity);
+	if (ret)
+		return ret;
+
+	return max597x_set_vp(rdev, lim_uV, severity, enable, false);
+}
+
+static int max597x_set_ovp(struct regulator_dev *rdev, int lim_uV, int severity,
+			   bool enable)
+{
+	int ret;
+
+	/*
+	 * MAX5970 has enable control as a special value in limit reg. Can't
+	 * set limit but keep feature disabled or enable W/O given limit.
+	 */
+	if ((lim_uV && !enable) || (!lim_uV && enable))
+		return -EINVAL;
+
+	ret = max597x_uvp_ovp_check_mode(rdev, severity);
+	if (ret)
+		return ret;
+
+	return max597x_set_vp(rdev, lim_uV, severity, enable, true);
+}
+
+static int max597x_set_ocp(struct regulator_dev *rdev, int lim_uA,
+			   int severity, bool enable)
+{
+	int val, reg;
+	unsigned int vthst, vthfst;
+
+	struct max5970_regulator *data = rdev_get_drvdata(rdev);
+	int rdev_id = rdev_get_id(rdev);
+	/*
+	 * MAX5970 doesn't has enable control for ocp.
+	 * If limit is specified but enable is not set then hold the value in
+	 * variable & later use it when ocp needs to be enabled.
+	 */
+	if (lim_uA != 0 && lim_uA != data->lim_uA)
+		data->lim_uA = lim_uA;
+
+	if (severity != REGULATOR_SEVERITY_PROT)
+		return -EINVAL;
+
+	if (enable) {
+
+		/* Calc Vtrip threshold in uV. */
+		vthst =
+		    div_u64(mul_u32_u32(data->shunt_micro_ohms, data->lim_uA),
+			    1000000);
+
+		/*
+		 * As recommended in datasheed, add 20% margin to avoid
+		 * spurious event & passive component tolerance.
+		 */
+		vthst = div_u64(mul_u32_u32(vthst, 120), 100);
+
+		/* Calc fast Vtrip threshold in uV */
+		vthfst = vthst * (MAX5970_FAST2SLOW_RATIO / 100);
+
+		if (vthfst > data->irng) {
+			dev_err(&rdev->dev, "Current limit out of range\n");
+			return -EINVAL;
+		}
+		/* Fast trip threshold to be programmed */
+		val = div_u64(mul_u32_u32(0xFF, vthfst), data->irng);
+	} else
+		/*
+		 * Since there is no option to disable ocp, set limit to max
+		 * value
+		 */
+		val = 0xFF;
+
+	reg = MAX5970_REG_DAC_FAST(rdev_id);
+
+	return regmap_write(rdev->regmap, reg, val);
+}
+
+static int max597x_get_status(struct regulator_dev *rdev)
+{
+	int val, ret;
+
+	ret = regmap_read(rdev->regmap, MAX5970_REG_STATUS3, &val);
+	if (ret)
+		return ret;
+
+	if (val & MAX5970_STATUS3_ALERT)
+		return REGULATOR_STATUS_ERROR;
+
+	ret = regulator_is_enabled_regmap(rdev);
+	if (ret < 0)
+		return ret;
+
+	if (ret)
+		return REGULATOR_STATUS_ON;
+
+	return REGULATOR_STATUS_OFF;
+}
+
+static const struct regulator_ops max597x_switch_ops = {
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.get_status = max597x_get_status,
+	.set_over_voltage_protection = max597x_set_ovp,
+	.set_under_voltage_protection = max597x_set_uvp,
+	.set_over_current_protection = max597x_set_ocp,
+};
+
+static int max597x_dt_parse(struct device_node *np,
+			    const struct regulator_desc *desc,
+			    struct regulator_config *cfg)
+{
+	struct max5970_regulator *data = cfg->driver_data;
+	int ret = 0;
+
+	ret =
+	    of_property_read_u32(np, "shunt-resistor-micro-ohms",
+				 &data->shunt_micro_ohms);
+	if (ret < 0)
+		dev_err(cfg->dev,
+			"property 'shunt-resistor-micro-ohms' not found, err %d\n",
+			ret);
+	return ret;
+
+}
+
+#define MAX597X_SWITCH(_ID, _ereg, _chan, _supply) {     \
+	.name            = #_ID,                         \
+	.of_match        = of_match_ptr(#_ID),           \
+	.ops             = &max597x_switch_ops,          \
+	.regulators_node = of_match_ptr("regulators"),   \
+	.type            = REGULATOR_VOLTAGE,            \
+	.id              = MAX597X_##_ID,                \
+	.owner           = THIS_MODULE,                  \
+	.supply_name     = _supply,                      \
+	.enable_reg      = _ereg,                        \
+	.enable_mask     = CHXEN((_chan)),               \
+	.of_parse_cb	 = max597x_dt_parse,		 \
+}
+
+static const struct regulator_desc regulators[] = {
+	MAX597X_SWITCH(SW0, MAX5970_REG_CHXEN, 0, "vss1"),
+	MAX597X_SWITCH(SW1, MAX5970_REG_CHXEN, 1, "vss2"),
+};
+
+static int max597x_regmap_read_clear(struct regmap *map, unsigned int reg,
+				     unsigned int *val)
+{
+	int ret;
+
+	ret = regmap_read(map, reg, val);
+	if (ret)
+		return ret;
+
+	if (*val)
+		return regmap_write(map, reg, *val);
+
+	return 0;
+}
+
+static int max597x_irq_handler(int irq, struct regulator_irq_data *rid,
+			       unsigned long *dev_mask)
+{
+	struct regulator_err_state *stat;
+	struct max5970_regulator *d = (struct max5970_regulator *)rid->data;
+	int val, ret, i;
+
+	ret = max597x_regmap_read_clear(d->regmap, MAX5970_REG_FAULT0, &val);
+	if (ret)
+		return REGULATOR_FAILED_RETRY;
+
+	*dev_mask = 0;
+	for (i = 0; i < d->num_switches; i++) {
+		stat = &rid->states[i];
+		stat->notifs = 0;
+		stat->errors = 0;
+	}
+
+	for (i = 0; i < d->num_switches; i++) {
+		stat = &rid->states[i];
+
+		if (val & UV_STATUS_CRIT(i)) {
+			*dev_mask |= 1 << i;
+			stat->notifs |= REGULATOR_EVENT_UNDER_VOLTAGE;
+			stat->errors |= REGULATOR_ERROR_UNDER_VOLTAGE;
+		} else if (val & UV_STATUS_WARN(i)) {
+			*dev_mask |= 1 << i;
+			stat->notifs |= REGULATOR_EVENT_UNDER_VOLTAGE_WARN;
+			stat->errors |= REGULATOR_ERROR_UNDER_VOLTAGE_WARN;
+		}
+	}
+
+	ret = max597x_regmap_read_clear(d->regmap, MAX5970_REG_FAULT1, &val);
+	if (ret)
+		return REGULATOR_FAILED_RETRY;
+
+	for (i = 0; i < d->num_switches; i++) {
+		stat = &rid->states[i];
+
+		if (val & OV_STATUS_CRIT(i)) {
+			*dev_mask |= 1 << i;
+			stat->notifs |= REGULATOR_EVENT_REGULATION_OUT;
+			stat->errors |= REGULATOR_ERROR_REGULATION_OUT;
+		} else if (val & OV_STATUS_WARN(i)) {
+			*dev_mask |= 1 << i;
+			stat->notifs |= REGULATOR_EVENT_OVER_VOLTAGE_WARN;
+			stat->errors |= REGULATOR_ERROR_OVER_VOLTAGE_WARN;
+		}
+	}
+
+	ret = max597x_regmap_read_clear(d->regmap, MAX5970_REG_FAULT2, &val);
+	if (ret)
+		return REGULATOR_FAILED_RETRY;
+
+	for (i = 0; i < d->num_switches; i++) {
+		stat = &rid->states[i];
+
+		if (val & OC_STATUS_WARN(i)) {
+			*dev_mask |= 1 << i;
+			stat->notifs |= REGULATOR_EVENT_OVER_CURRENT_WARN;
+			stat->errors |= REGULATOR_ERROR_OVER_CURRENT_WARN;
+		}
+	}
+
+	ret = regmap_read(d->regmap, MAX5970_REG_STATUS0, &val);
+	if (ret)
+		return REGULATOR_FAILED_RETRY;
+
+	for (i = 0; i < d->num_switches; i++) {
+		stat = &rid->states[i];
+
+		if ((val & MAX5970_CB_IFAULTF(i))
+		    || (val & MAX5970_CB_IFAULTS(i))) {
+			*dev_mask |= 1 << i;
+			stat->notifs |=
+			    REGULATOR_EVENT_OVER_CURRENT |
+			    REGULATOR_EVENT_DISABLE;
+			stat->errors |=
+			    REGULATOR_ERROR_OVER_CURRENT | REGULATOR_ERROR_FAIL;
+
+			/* Clear the sub-IRQ status */
+			regulator_disable_regmap(stat->rdev);
+		}
+	}
+	return 0;
+}
+
+static int max597x_adc_range(struct regmap *regmap, const int ch,
+			     u32 *irng, u32 *mon_rng)
+{
+	unsigned int reg;
+	int ret;
+
+	/* Decode current ADC range */
+	ret = regmap_read(regmap, MAX5970_REG_STATUS2, &reg);
+	if (ret)
+		return ret;
+	switch (MAX5970_IRNG(reg, ch)) {
+	case 0:
+		*irng = 100000;	/* 100 mV */
+		break;
+	case 1:
+		*irng = 50000;	/* 50 mV */
+		break;
+	case 2:
+		*irng = 25000;	/* 25 mV */
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* Decode current voltage monitor range */
+	ret = regmap_read(regmap, MAX5970_REG_MON_RANGE, &reg);
+	if (ret)
+		return ret;
+
+	*mon_rng = MAX5970_MON_MAX_RANGE_UV >> MAX5970_MON(reg, ch);
+
+	return 0;
+}
+
+static int max597x_setup_irq(struct device *dev,
+			     int irq,
+			     struct regulator_dev *rdevs[MAX5970_NUM_SWITCHES],
+			     int num_switches, struct max5970_regulator *data)
+{
+	struct regulator_irq_desc max597x_notif = {
+		.name = "max597x-irq",
+		.map_event = max597x_irq_handler,
+		.data = data,
+	};
+	int errs = REGULATOR_ERROR_UNDER_VOLTAGE |
+	    REGULATOR_ERROR_UNDER_VOLTAGE_WARN |
+	    REGULATOR_ERROR_OVER_VOLTAGE_WARN |
+	    REGULATOR_ERROR_REGULATION_OUT |
+	    REGULATOR_ERROR_OVER_CURRENT |
+	    REGULATOR_ERROR_OVER_CURRENT_WARN | REGULATOR_ERROR_FAIL;
+	void *irq_helper;
+
+	/* Register notifiers - can fail if IRQ is not given */
+	irq_helper = devm_regulator_irq_helper(dev, &max597x_notif,
+					       irq, 0, errs, NULL,
+					       &rdevs[0], num_switches);
+	if (IS_ERR(irq_helper)) {
+		if (PTR_ERR(irq_helper) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+
+		dev_warn(dev, "IRQ disabled %pe\n", irq_helper);
+	}
+
+	return 0;
+}
+
+static int max597x_regulator_probe(struct platform_device *pdev)
+{
+	struct max5970_data *max597x;
+	struct regmap *regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	struct max5970_regulator *data;
+	struct i2c_client *i2c = to_i2c_client(pdev->dev.parent);
+	struct regulator_config config = { };
+	struct regulator_dev *rdev;
+	struct regulator_dev *rdevs[MAX5970_NUM_SWITCHES];
+	int num_switches;
+	int ret, i;
+
+	if (!regmap)
+		return -EPROBE_DEFER;
+
+	max597x = devm_kzalloc(&i2c->dev, sizeof(struct max5970_data), GFP_KERNEL);
+	if (!max597x)
+		return -ENOMEM;
+
+	i2c_set_clientdata(i2c, max597x);
+
+	if (of_device_is_compatible(i2c->dev.of_node, "maxim,max5978"))
+		max597x->num_switches = MAX5978_NUM_SWITCHES;
+	else if (of_device_is_compatible(i2c->dev.of_node, "maxim,max5970"))
+		max597x->num_switches = MAX5970_NUM_SWITCHES;
+	else
+		return -ENODEV;
+
+	i2c_set_clientdata(i2c, max597x);
+	num_switches = max597x->num_switches;
+
+	for (i = 0; i < num_switches; i++) {
+		data =
+		    devm_kzalloc(&i2c->dev, sizeof(struct max5970_regulator),
+				 GFP_KERNEL);
+		if (!data)
+			return -ENOMEM;
+
+		data->num_switches = num_switches;
+		data->regmap = regmap;
+
+		ret = max597x_adc_range(regmap, i, &max597x->irng[i], &max597x->mon_rng[i]);
+		if (ret < 0)
+			return ret;
+
+		data->irng = max597x->irng[i];
+		data->mon_rng = max597x->mon_rng[i];
+
+		config.dev = &i2c->dev;
+		config.driver_data = (void *)data;
+		config.regmap = data->regmap;
+		rdev = devm_regulator_register(&i2c->dev,
+					       &regulators[i], &config);
+		if (IS_ERR(rdev)) {
+			dev_err(&i2c->dev, "failed to register regulator %s\n",
+				regulators[i].name);
+			return PTR_ERR(rdev);
+		}
+		rdevs[i] = rdev;
+		max597x->shunt_micro_ohms[i] = data->shunt_micro_ohms;
+	}
+
+	if (i2c->irq) {
+		ret =
+		    max597x_setup_irq(&i2c->dev, i2c->irq, rdevs, num_switches,
+				      data);
+		if (ret) {
+			dev_err(&i2c->dev, "IRQ setup failed");
+			return ret;
+		}
+	}
+
+	return ret;
+}
+
+static struct platform_driver max597x_regulator_driver = {
+	.driver = {
+		.name = "max5970-regulator",
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+	},
+	.probe = max597x_regulator_probe,
+};
+
+module_platform_driver(max597x_regulator_driver);
+
+
+MODULE_AUTHOR("Patrick Rudolph <patrick.rudolph@9elements.com>");
+MODULE_DESCRIPTION("MAX5970_hot-swap controller driver");
+MODULE_LICENSE("GPL v2");